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Using hot-vapor bypass for pressure control in distillation columns

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Chinese Journal of Chemical Engineering 2018年第1期26卷 144-151页

作者： Stefano Ciannella Arthur Siqueira Damasceno Icaro Caze nunes Gilvan Wanderley de Farias Neto Wagner Brandao Ramos Romildo Pereira Brito Department of Chemical Engineering Federal University of Campina GrandeCarnpina Grande 58109-970ParafbaBrazil

Distillation column control is widely explored in literature due to its complexity and importance in chemical and petrochemical industries. In this process, pressure represents one of the most important variables to be controlled. However, there are few studies about how pressure affects the dynamic behavior of distillation columns and most research on distillation column control involve direct manipulation of cooling fluid through the condenser. Nevertheless, such an approach demands constant changes in cooling fluid flowrates that are commonly by the order of tons per hour, which can be difficult to work or even unfeasible in a real plant. Furthermore, this strategy is usually avoided, as it can cause fouling and corrosion acceleration. the hot-vapor bypass strategy fits well as a solution for these issues, eliminating the need to dynamically manipulate cooling fluid flowrates in the condensation unit. this work presents the modeling and simulation of a conventional distillation column for the separation of water and ethanol, in which a comparative study between a conventional pressure control and a control using hot-vapor bypass was performed. the main results were obtained through dynamic simulations which considered various disturbances in the feed stream, and demonstrated superior performance by the hot-vapor bypass system over the usual scheme proposed in literature, while evaluating the lntegral Absolute Error （IAE） norm as the control performance index.

关键词： Distillation Pressure control Hot-vapor bypass

Modelling the role of ground-true riparian vegetation for providing regulating services in a Mediterranean watershed

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International Soil and Water Conservation Research 2023年第1期11卷 159-168页

作者： Bruno A.Aparício João Pedro nunes Léonard Bernard-Jannin Luis Filipe Dias Andre Fonseca teresa Ferreira cE3c-Centre for Ecology Evolution and Environmental Changes&CHANGE-Global Change and Sustainability InstituteFaculty of SciencesUniversity of LisbonLisbonPortugal Forest Research Centre&Laboratory tERRA School of AgricultureUniversity of LisbonLisbonPortugal Soil Physics and Land Management Group Wageningen University and ResearchWageningenNetherlands Longline Environment Ltd LondonUK

Intensive agricultural and industrial activities are often considered major sources of water ***,riparian vegetation(RV)is increasingly being promoted as a solution to balance the potentially adverse effects that agriculture may have on water ***,existing RV is often overlook in recent modelling efforts,failing to capture the current amount of ecosystem services ***,we used the Soil and Water Assessment tool ecohydrological model to simulate the influence of ground-true RV on i)nutrient(nitrate and total phosphorus)and sediment exports from agricultural areas and ii)its effect for in-stream *** results are further compared against a set of hypothetical scenarios of different RV widths and different *** results point to a great rele-vance of existing RV in controlling in-stream concentration of sediments and nutrients where pressure from agriculture is highest,preventing them to surpass limits set in the EU Water Framework *** the other hand,in areas with industry discharges,the role of RV is limited and model results suggest that restoring RV would have limited *** illustrate how existing RV may already provide strong but not acknowledged water quality regulation services,how these services can differ substantially between nearby streams,and that effective strategies to improve water quality using RV must acknowledge existing patterns of vegetation,land use and contamination sources.

关键词： Agricultural pollution Riparian vegetation Ecosystem services Hydrological services Mediterranean region

Capsule enteroscopy is useful for the therapeutic management of Crohn's disease

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World Journal of Gastroenterology 2015年第44期21卷 12660-12666页

作者： Joao Santos-Antunes Hélder Cardoso Susana Lopes Margarida Marques Amadeu CR nunes Guilherme Macedo Gastroenterology Department Faculty of Medicine Hospital de Sao Joao Department of Biochemistry (U38-FCt) Faculty of Medicine University of Porto

AIM: to analyze therapeutic changes in Crohn's disease(CD) patients following video capsule endoscopy(VCE) and to assess the usefulness of Lewis score and the Patency ***: Patency Capsule was performed in every patient that had indication for VCE, and those with negative patency did not undergo VCE. Patients with established CD that underwent VCE between January 2011 and February 2014 were selected for this study; those with suspected CD were excluded, independent of VCE results, since our purpose was to address differences in therapeutic regimen in CD patients before and after VCE. Patients with inconclusive VCE were also excluded. Patients had to be free of non-steroidal anti-inflammatories for at least 1 mo. those patients who met these criteria were allocated into one of three groups: Staging group(asymptomatic CD patients that underwent VCE for staging of CD), Flare group(patients with active CD), or Post-op group(CD patients evaluated for post-operative recurrence). Lewis score was calculated for every VCE procedure. Statisticalanalysis was performed to address the impact of VCE findings on the therapeutic management of CD patients and to evaluate the utility of the Lewis ***: From a total of 542 VCEs, 135 were performed in patients with CD. Patency capsule excluded nearly 25% of the patients who were supposed to undergo VCE. No videocapsule retention during VCE was reported. From these 135 patients, 29 were excluded because CD diagnosis was not established at the time of VCE. therefore, a total of 106 patients were included in the final analysis. From these, the majority were in the Staging group(n = 73, 69%), and the remaining were in the Flare(n = 23, 22%) or Post-op(n = 10, 9%) group. Median time between diagnosis and VCE was 5.5 years. Overall, VCE determined changes in the treatment of 40% of patients: only 21% remained free of immunosuppressors after VCE compared to 44% before VCE(P the differences in therapy before and a

关键词： Capsule enteroscopy Crohn's disease treatment modification Patency capsule Lewis score

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春沐源恐龙岛水乐园——热带雨林中的畅想曲

风景园林 2025年第2期32卷 54-58页

作者：张唐景观张唐景观

1背景春沐源小镇是一个位于广东省河源市的旅游胜地。2018年,张唐景观以河源恐龙化石文化为主题,在河边设计了约2.5 hm^(2)的龙骨乐园。2023年底,启动了一个以戏水为主题的乐园建设项目,选址位于龙骨乐园河对岸,用地面积约7000 m^(2)。... 详细信息

1背景春沐源小镇是一个位于广东省河源市的旅游胜地。2018年,张唐景观以河源恐龙化石文化为主题,在河边设计了约2.5 hm^(2)的龙骨乐园。2023年底,启动了一个以戏水为主题的乐园建设项目,选址位于龙骨乐园河对岸,用地面积约7000 m^(2)。设计概念来源于河源万绿湖的卫星图。河源市处于粤东北山区与珠江三角洲平原地区的结合部,粤赣边境山高岭峻,东江、新丰江纵贯全境,山岭与盆地相间,在山间和东江边分布着冲积平原和宽广的谷地。南岭山脉逐渐向平原过渡,形成湖岛交织的风貌特征。

关键词：南岭山脉用地面积珠江三角洲平原风貌特征广东省河源市恐龙化石万绿湖河对岸

Prevalence and factors associated with stages of behavior change for physical activity in adolescents:a systematic review

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World Journal of Pediatrics 2017年第3期13卷 202-209页

作者： Heloyse Elaine Gimenes nunes Diego Augusto Santos Silva Eliane Cristina de Andrade Gon(c)alves Federal University of Santa Catarina Post-Graduate Program in Physical EducationFlorianópolisSanta CatarinaBrazil

Background:to analyze prevalence and factors associated with stages of behavior change for physical activity in *** sources:A search was performed in SciELO,PubMed,PsycINFO,SPORtDiscus and *** search terms were 'behavior change' OR 'stages of change' OR 'stages of readiness' OR 'readiness to change' OR 'transtheoretical model' OR 'process to change' OR 'decisional balance',and 'motor activity' OR 'physical activity' OR 'physical exercise' and 'adolescent' OR 'students'.After the eligibility criteria,18 articles were ***:the highest prevalence of adolescents in the precontemplation,contemplation,and preparation stages was found in the Germany,South Korea,and Iran while there were more adolescents in the action and maintenance in South Korea and *** evidence of association indicated that females are more likely to be in precontemplation,contemplation and *** evidence was inconclusive for age (in relation to the precontemplation,contemplation,action and maintenance stages),economic status (all stages),shift of study (when stratified by gender) and body composition (all stages).No association was found with parental level of ***:the findings can help to guide interventions and further research on the topic of behavior changes for physical activity in adolescents.

关键词： adolescent behavior motor activity students transtheoretical model

Immunohistochemical expression of matrix metalloproteinase-9 and 13 in oral squamous cell carcinoma and their role in predicting lymph node metastasis

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World Journal of Methodology 2025年第2期15卷 108-116页

作者： Bhari Sharanesha Manjunatha Keshav t Handge Vandana Sandeep Shah Yasser Eid Al-thobaiti Deepak Gowda Sadashivappa Pateel Department of Basic Oral Medicine and Allied Dental Sciences Taif UniversityAt`Taif 26571MakkahSaudi Arabia Department of Oral and Maxillofacial Pathology Dr.Vasantrao Pawar Medical CollegeHospital and Research CentreNashik 423101MaharashtraIndia Department of Oral Pathology and Microbiology KM Shah Dental College and HospitalSumandeep VidyapeethVadodara 391760GujaratIndia Department of Oral and Maxillofacial Surgery and Diagnostic Sciences Faculty of DentistryTaif UniversityAl-Haweiah 26571 MakkahSaudi Arabia Department of Oral Pathology and Microbiology Faculty of DentistryMAHSA UniversitySelangor 42610Malaysia

BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ***-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific ***-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of *** MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant *** to assess the immunohistochemical expression of MMP-9 and MMP-13 in *** A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective *** protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive *** the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical *** Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor *** majority of the patients were in advanced tNM stages(III and IV),and showed intense expression of MMP-9 and *** the present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and *** expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with t

关键词： Matrix metalloproteinases Oral squamous cell carcinoma tumor staging Immunohistochemistry Invasion Lymph node metastasis tNM stage

Doxycycline induces bone repair and changes in Wnt signalling

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International Journal of Oral Science 2017年第3期9卷 158-166页

作者： kátia do nascimento gomes ana paula negreiros nunes alves paula góes pinheiro dutra glauce socorro de barros viana faculty of dentistry pharmacy and nursingfederal university of cearáFortalezaBrazil faculty of medicine federal university of cearáFortaleza Brazil

Doxycycline （DOX） exhibits anti-inflammatory and MMP inhibitory properties. the objectives of this study were to evaluate the effects of DOX on alveolar bone repair. Controls （CtL） and DOX-treated （10 and 25 mg. kg- 1） molars were extracted, and rats were killed 7 or 14 days later. the maxillae were processed and subjected to histological and immunohistochemical assays. Hematoxylin-eosin staining （7th day） revealed inflammation in the CtL group that was partly reversed after DOX treatment. On the 14th day, the CtL group exhibited bone neoformation, conjunctive tissue, re-epithelization and the absence of inflammatory infiltrate. DOX-treated groups exhibited complete re-epithelization, tissue remodelling and almost no inflammation. Picrosirius red staining in the DOXlO group （7th and 14th days） revealed an increased percentage of type I and III collagen fibres compared with the CtL and DOX25 groups. the DOXlO and DOX25 groups exhibited increases in osteoblasts on the 7th and 14th days. However, there were fewer osteoclasts in the DOXlO and DOX25 groups on the 7th and 14th days. Wnt-lOb- immunopositive cells increased by 130% and 150% on the 7th and 14th days, respectively, in DOX-treated groups compared with the CtL group. On the 7th day, Dickkopf （Dkk）-I immunostaining was decreased by 63% and 46% in the DOXlO and DOX25 groups, respectively. On the 14th day, 69% and 42% decreases in immunopositive cells were observed in the DOXlO and DOX25 groups, respectively, compared with the CtL group. By increasing osteoblasts, decreasing osteoclasts, activating Wnt lOb and neutralising Dkk, DOX is a potential candidate for bone repair in periodontal diseases.

关键词： alveolar bone loss bone diseases bone repair doxycycline Dickkopf-1 immunohistochemistry Wnt-lOb

transjugular intrahepatic portosystemic shunt for Budd-Chiari syndrome:A comprehensive review

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World Journal of Gastroenterology 2020年第34期26卷 5060-5073页

作者： Riccardo Inchingolo Alessandro Posa Martin Mariappan tiago Kojun tibana thiago Franchi nunes Stavros Spiliopoulos Elias Brountzos Interventional Radiology Unit "F.Miulli"Regional HospitalAcquaviva delle Fonti 70021Italy Department of Radiology King´s College HospitalLondon SE59RSUnited Kingdom Department of Radiology Gemelli HospitalRoma 00135Italy Interventional Radiology Department Aberdeen Royal Infirmary HospitalAberdeen AB252ZNUnited Kingdom Interventional Radiology Department Universidade Federal de Mato Grosso do SulCampo Grande 79070-900Brazil 2nd Department of Radiology School of MedicineNational and Kapodistrian University of AthensChaidari Athens GR 12461Greece

Budd-Chiari syndrome(BCS)is a relatively rare clinical condition with a wide range of symptomatology,caused by the obstruction of the hepatic venous *** left untreated,it has got an high mortality *** management is based on a step-wise approach,depending on the clinical presentation,and includes different treatment from anticoagulation therapy up to Interventional Radiology techniques,such as transjugular intrahepatic portosystemic shunt(tIPS).tIPS is today considered a safe and highly effective treatment and should be recommended for BCS patients,including those awaiting orthotopic liver *** this review the pathophysiology,diagnosis and treatment options of BCS are presented,with a special focus on published data regarding the techniques and outcomes of tIPS for the treatment of ***,unresolved issues and future research will be discussed.

关键词： Budd-Chiari syndrome Liver transjugular intrahepatic portosystemic shunt Orthotopic liver transplantation Interventional radiology Portal hypertension

Impact of Injection Strategies and Jatropha Biodiesel-Diesel Blends on Soot and Emissions

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Energy Engineering 2025年第3期122卷 929-941页

作者： Mohammed A.Fayad Amera A.Radhi Marwa K.Abood Hind A.AL Salihi Miqdam t.Chaichan Energy and Renewable Energies technology Center University of Technology-IraqKaradaBaghdad35050Iraq Department of Applied Sciences University of Technology-IraqBaghdad35050Iraq

Oxygenated fuels can reduce harmful emissions without affecting engine performance,meeting the big challenge in the transportation industry,which keeps the environment safe and reduces global *** study investigates the impact of biodiesel injection strategies and fuel injection pressures(FIP)on diesel engine exhaust emission *** engine is fuelled with 20%Jatropha biodiesel(JB)and 80%diesel,named *** ratios of fuel injection pressures started with injecting the fuel(diesel and JB20D)from 200 bar to 500 *** experimental outcomes indicate that the engine performance of brake-specific fuel consumption increased by 21.36%from the burning of JB20D compared with diesel,while brake thermal efficiency improved by 6.54%for low and high FIP compared to the *** high fuel injection pressures slightly decrease the nitrogen oxide(NOX)emissions for both diesel and *** emissions of NOX decreased from the combustion of JB20D by 18.7%under high fuel injection pressures compared to *** concentration of soot particulate decreased by 20.4%form JB20D combustion than those combusted from diesel fuel.

关键词： Particulate matter fuel injection pressure soot nanoparticles smoke number diffusion flame